My first stacked image of the Moon

[nfotis]

From yesterday night, I experimented with my ASI462 and my Skymax 127 on a HEQ5 mount.

Recorded 4000 video frames, used 15% of the frames in the second quarter of images with Autostakkert!3. Used a ZWO IR pass filter, getting a reddish hue of the video/stacked image, then I used Levels in GIMP to bring up the green and blue channels (I kept the red as is).

The Youtube video shows the recording from the camera (I captured at 136-140 FPS on my Thinkpad T480, as RAW AVI video, so you should play it back as fast as possible, to get a sense of the air disturbances)

 

 

The resulting stacked and sharpened images from AS!3 are below, together with the colour corrected version (exported as JPEG files from GIMP).

Suggestions for improvement are welcome.

 

Cheers,

N.F.

[wouterdhoye]

very nice. Good capture, and good processing. Well done 👍 

[nfotis]

Thank you, I am still learning AS!3, I tried stacking some dSLR images (converted via PIPP to an AVI file), but I am getting mixed results.

How many pictures is a minimum to stack? Ten? Twenty?

N.F.

 

[wouterdhoye]

The point of stacking is in fact to reduce noise. software like autostakkert on top of that will also asses the quality and only use the best images for the stacksize you selected. Now, how many frames you need in a stack depends on the noise level in the single frames. The more noise in the frames the more you will need to reduce it. 

Now to reduce the noise by 50% you need 4 times as many frames. So the sequence is like 1 - 4 - 16 - 64 - 256,.... and so on. As it is so camera dependent All i can advise you to do is experiment and try different stack sizes in Autostakkert. With my ASI 174MM i tended to use 500 frame stack sizes to get noise to acceptable levels for high res work, and then during post processing still some noise reduction was necessary to keep the residual noise in check. With my new QHY 462, 200 frames stack requires only very very mild noise reduction and to some no noise reduction in post processing at all.

So experiment, you have the data.. 

Clear skies,

Wouter.

[Ouroboros]

Am I right in thinking that stacking lunar software does not correct images for distortion? 

[wouterdhoye]

I f you mean distortion by seeing, then yes, autostakkert will correct for distorion by using hundreds or even thousands of alignment points in an image. correcting the placement of these alignment points corrects for distortion or in fact displacement between individual frames. 

Wouter.

[Ouroboros]

8 minutes ago, wouterdhoye said:

I f you mean distortion by seeing, then yes, autostakkert will correct for distorion by using hundreds or even thousands of alignment points in an image. correcting the placement of these alignment points corrects for distortion or in fact displacement between individual frames. 

Wouter.

OK. Thanks.  As you can tell I’m not a lunar/planetary imager.  

[wouterdhoye]

6 minutes ago, Ouroboros said:

OK. Thanks.  As you can tell I’m not a lunar/planetary imager.  

we all have to start somewhere. 😀

[Ouroboros]

1 minute ago, wouterdhoye said:

we all have to start somewhere. 😀

Yeah, I suppose we do. Actually I’ve been imaging about 10 years, just not planetary or lunar. Well, I’ve dabbled from time to time on the latter. 

[nfotis]

41 minutes ago, Ouroboros said:

Yeah, I suppose we do. Actually I’ve been imaging about 10 years, just not planetary or lunar. Well, I’ve dabbled from time to time on the latter. 

 

The good thing is, we can focus (literally) on lunar photography when the moon makes harder to shoot DSO objects.  So, that's one more target to hit 🙂

After all, there are so many details to discern with the help of a long focal length scope.

N.F.

 

[nfotis]

Tonight, I processed one more video (Skymax 127, ASI462MC, IR pass filter, HEQ5 Pro mount).

The head-on lighting on Tycho was more flat than the previous side-lit photo, and I think that I rode the highlight slider a bit much at the end?

I used AS!3 again for the stacking, a really nice program (I am still trying to learn it, watching now the creator's interview on Youtube).

Used different options on PIPP for the video conversion from the original 8 GB file  to the 330 MB MPEG file for a Youtube upload, so the colors are more correct.

 

The reddish images come from AS!3, while the color corrected one is due to Picasa. Converted to JPEG for faster upload/viewing.

Suggestions and ideas are welcome.

N.F.

 

 

[Sunshine]

Nice work!!

[nfotis]

Thank you, still learning the ropes myself.

Fortunately, the moon is such a bright target that's not hard to shoot (when it's not cloudy) here in Athens. Hope to raise my level to planetary imaging soon (as long as the planets return over the horizon for us in the northern hemisphere)

If everything goes well, I may try with DSO objects later (but the light pollution in the city would mean a costly set of filters and cameras and whatnot). We'll see...

N.F.

 

[nfotis]

A comparison with a shot using an IR-cut filter might be useful (from the same night).

The white balance wasn't tampered with. Only stacked the 15% best frames from a 4000 frames RAW AVI video, then opened up the dark places.

 

N.F.

 

[neil phillips]

Well done on your first stacked image. Nicely done

[nfotis]

Thank you. I am wondering if I should up the contrast a bit, but these look quite pleasing to my eyes. I think that even the IR cut version is quite good (and I didn't have to mess with white balance/colour correction after the processing).

Need to correct things on my capture sequence (I learned after the fact that Sharpcap can do automatic white balance as well). After I settle, I may attempt a mosaic of the full moon disk as well (a larger version of the IMX462 would be quite helpful, but I think that an IMX492MM in the 47 megapixels mode would be quite something)

N.F.